﻿#region License
/* ---------------------------------------------------------------- *
 *
 * This file is part of the API Concepts Framework
 * http://apiconceptsframework.codeplex.com
 *
 * Copyright (C) 2014 eva Kühn, Thomas Scheller, Vienna University of Technology
 * http://www.complang.tuwien.ac.at/eva
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program. If not, see http://www.gnu.org/licenses/
 *
 * ---------------------------------------------------------------- */
#endregion

using System;
using System.Collections.Generic;

namespace ApiConceptsFramework
{
	static class DistinctExtensions
	{
		public static IEnumerable<T> Distinct<T, TCompare>(this IEnumerable<T> values, Func<T, TCompare> getDistinctValue)
		{
			var uniqueValues = new List<TCompare>();
			foreach (var value in values)
			{
				var uniqueValue = getDistinctValue(value);
				if (!uniqueValues.Contains(uniqueValue))
				{
					uniqueValues.Add(uniqueValue);
					yield return value;
				}
			}
		}
	}
}